Ok seems dead in here so I'll do a response. I have considered a tool changer but never went past that. My Torus Pro uses an acorn instead of the original Mach 3 based control. Centroid does provide some built in macros for tool changers. Depending on the operation of the tool changer it may be simple or require a slight PLC modification. It also might be hard. I'm not sure.
I would like to hear from anyone who tried one of the generic tool changers. If the quality is ok it might be worth doing. I have a few extra inputs and outputs on the acorn.